(a) Field of the Invention
The present invention relates to an FSK (frequency shift keying) receiving apparatus and method in a smart utility network system, and more particularly, to a receiving apparatus and method based on FSK modulation.
(b) Description of the Related Art
Recently, much emphasis has been placed on the importance of AMI (advanced metering infrastructure) energy management systems, which improve energy consumption efficiency and provides a comfortable living environment by enabling two-way communication of real-time utility usage data for electricity, water, and gas between utility providers and consumers.
Up to now, active research has been conducted on telemetering systems for remotely measuring and monitoring utility usage from electricity, water, and gas meters, based on PLC and ZigBee technologies. However, ZigBee wireless technology has difficulty in obtaining a high link margin in a poor utility network communication environment, and there are limitations in merging ZigBee with mesh routing techniques in a remote outdoor environment. Accordingly, utility service providers in the U.S. established the IEEE 802.15.4g SUN (smart utility network) radio transmission technology standard, which is a new global standard linked to a smart grid.
A physical layer for the IEEE 802.15.4g SUN radio transmission technology standard utilizes narrow-band FSK modulation techniques, and such narrow-band FSK modulation techniques are optimized for smart-grid AMI systems because the communication distance is greater than 1 km owing to their narrowband characteristics.
However, FSK modulation systems vary in performance depending on the receiving method, and therefore the receiver sensitivity associated with the maximum communication distance may be low, and it may be difficult to extract information for channel scan, CCA (clear channel access), etc. used to run an AMI system in an IEEE 802.15.4g SUN standard-based network. This brings out the need for an FSK modulation method which is suitable for a SUN networking environment for a smart grid.